Electrical connectors for coaxial cables



Oct. 15, 1963 R. A. KEIL 3,107,135

ELECTRICAL CONNECTORS FCR COAXIAL CABLES Filed April 10, 1961 I 5 V- 1 IINVENTOR,

ROBERT A- KEIL,

ATTORNEY United States Patent 3,107,135 ELECTRICAL CONNECTORS FORCOAXIAL CABLES Robert A. Keil, Flushing, N.Y., assiguor to AutomaticMetal Products Corp., New York, N.Y., a corporation of New York FiledApr. 10, 1961, Ser. No. 101,921 Claims. (Cl. 339-403) The presentinvention relates to electrical connectors for solid dielectric-filledcoaxial cables and more particularly to the connector to be carried byan end of such cable for detachable connection to a mating terminal on awave signal apparatus or another cable end.

An object of this invention is to provide a novel and improved connectorof the class mentioned, which securely clamps the cable withoutindentation of the cable dielectric and hence without disturbance of thecables impedance characteristic. As to strength of the joint, thatafforded by this connector when cable diameter is up to aboutone-quarter inch, is sufiicient to withstand a pull on the cable greaterthan the inherent cable strength.

Another object thereof is to provide a novel and im proved connectorconstruction of the character set forth, afiording an effective sealagainst liquid and gas seepage at the clamping end. This is accomplishedby gaskets associated with means whereby their compression iscontrollable, and further, the structure is such that said gasketsautomatically effect a lock-nut action thereby avoiding any loosening ofthe locking member of the connector.

A further object thereof is to provide a connector of the typedescribed, which requires no special tools for assembly, which can beremoved and its clamping parts reused and which needs no combing,trimming or removal of the braid outer conductor or of the dielectrictherewithin, in preparation to mount the conductor onto the cable end.

Still a further object of this invention is to provide a novel andimproved connector of the kind described, having the mentionedattributes and which is reasonable in cost, simple and easy tomanipulate in mounting it or removing it and efficient in carrying outthe purposes for which it is designed.

Other objects and advantages will become apparent as this disclosureproceeds.

For the practice of this invention, my new connector consists of threeunitary parts, namely a body assembly, a contact wedge assembly and aclamp and seal assembly. I may here mention that the cable end on whichthe connector is to be mounted, is trimmed to expose a short extendinglength of its axial conductor. Also that the clamp and seal assembly isset as a sleeve on the cable away from its trimmed end. The contactwedge assembly is forced onto the cable end and includes a metalfunnelshaped part which enters into the tubular braid conductor of thecable While the exposed axial conductor piece is received into the endof a hollow metal pin insulatively carried within said funnel-shape,thus eiiecting electrical connection with the cables conductors. Theclamp and seal assembly is brought to receive said funnel-shape insideof it whereby a part of the last mentioned assembly cooperates with saidfunnel-shape to act as a clamp; such part also oiiering a stop to limitthe extent sealing gaskets are compressed so as to avoid indentation inthe cable. The body assembly receives said contact pin to extend axiallywithin a tubular terminal and the clamp and seal assembly is threadedlycoupled to said body assembly to form the connector into one structure.Other incidents of structure and a more detailed description of apreferred embodiment of this invention will now be set forth.

In the accompanying drawing forming part of this specification, similarcharacters of reference indicate corresponding parts in all the views.

3,107,135 Patented Oct. 15, 1963 ICC FIG. 1 is an exploded view showingthe three assemblies which comprise a preferred embodiment of thisinvention, drawn in perspective. a

FIG. 2 is an enlarged central section showing the contact wedge assemblymounted on the end of a cable which already carries the clamp and sealassembly.

FIG. 3 is a section like FIG. 2, showing the connector mounted for use.

In the drawing, the numeral 15 designates generally the connectormounted at the end of a coaxial cable denoted generally by the numeral16. The three principal parts of said connector are a contact wedgeassembly indicated genermly by the numeral 17, a clamp and seal assemblydenoted generally by the numeral 18 and a body assembly shown generallyby the numeral 19.

The contact wedge assembly 17 here shown, consists of a metalfunnel-shaped element designated generally by the numeral 20, whose stemis empty, but its frusto-conical tubular part 21 fixedly holds adielectric piece 22 through which is axially mounted a metal pin 25extending outwardly of part 21, the supported portion of said pin beinghollow and open at pin end which faces the stem 23 of said funnel-form.Let us consider for a moment that the clamp and seal assembly 18 whichis a tubular structure, is set as a sleeve on the cable 16 away from thecables end, where the cable has been trimmed to present a short length24' of its axial conductor 24. Now, admit the cables end into the hollowtubular stem 23 of the funnel-form so that the bare central wire piece24' enters the hollow in said pin 25 and the funnel stem 23 shall enterthe outer tubular braided conductor 26 of the cable until nearly theentire fr-usto-conical part 21 is within said hollow conductor tocontact same. The bore in the pin 25 is somewhat of greater diameterthan that of the conductor 24 away from the entrance to said bore, sothat the resulting interior space can be filled with solder 27 appliedthrough the gate hole 27 in the exposed pin body. Thus the contact wedgeassembly is firmly secured to the cable and electrical connection ismade with the respective conductors 24 and 26 to the in sulated parts 25and 20 of the said contact wedge as sembly.

The body assembly 19 here shown, includes a tubular member 28 having areduced end 28' which terminates in an outward flange 29. The largerportion of said tubular member 23 is interiorally threaded as indicatedat 28". Said body assembly has another tubular member 3d having areduced end 30. The larger end of member 30 is provided with an innerflange 31. Said tubular members 28 and 30 are telescopically associatedand relatively turnable; the flange 29 being within the larger portionof the tubular member 30. Resilient ring means 32 between said flanges,contact the same and acts to keep them apart whereby the flange 29 actsagainst a rubber sealing ring 33 which is against the step 34 Within thetubular member 30. The rim region 21 of the funnel-shape 20 iscylindrical and is in fitting contact with the interior surface of thereduced portion 28' of the tubular member 23. There is a tubularextension 35 fixed at the flanged end of the tubular member 28 and is anextension thereof extending to near the open end of the tubular member30. The sealing ring 33 fits on said tubular extension and suchextension 35 is lined with a dielectric sleeve 36 having an integralpartition 36 therein which creates the socket 37; said partition havinga central opening therethrough in and through which the pin 25 fits whenthe body assembly 19 is set to receive the contact wedge assembly 17. Itis evident that said metal pin 25 serves as the connectors terminal ofthe axial conductor 24 and that the metal tube 35 is the terminal of thetubular conductor 26 of the coaxial cable 16. L-slots 38 in the tubularpart 30 which swivels, are

for bayonet joint connection of the connector 15 to its mating part onapparatus or wire end to which the cable 16 is to be electricallyconnected to.

The clamp and seal assembly 18 here shown, includes a tubular screw 40for engagement with the-thread 28 of the tubular member .23 whereby theconnector 15 is made an assembled unit as shown in FIG. 3. This tubularscrew fits loose on the cable 16 and is counter-bored from the endthereof which enters said member 28. The interior wall of suchcounter-bore is provided with an annular groove 41, away from the seatof such counterbore. A washer 42 rests against such seat and there is aring gasket 4-3 resting against said washer, away from said groove 41.Said clamp and seal assembly also includes a ring 44 which extends partof its length into said counterbore in the tubular screw 40, restsagainst said ring gasket 43 and extends out of such counterbore andterminates here in an outward flange 44'. The flanged end of this ring44 is flared at 44-" to cooperate with the frusto-conical part 2 1 toclamp the cables tubular conductor 26 and the outer insulation covering45 between them. The surface of said part 21 may be serrated as shown at21' to aid the clamping action which occurs upon the assembly of theconnector 15 on the cables end as shown in FIG. 3. Against the back ofthe flange 44' there is a gasket ring 46 and against such gasket thereis a washer 47 adapted to be contacted by the inner end ring face of thetubular screw it). A protuberance 43 which may be an outward head onsaid clamping ring 44, extends into the annular groove 41 to maintainthe assembly of the components of the clamp and seal assembly it; andlimit the relative sliding movement of the parts 40 and 44. The gasketrings 43 and 46 are under compression, in FIG. 3.

The manner of mounting the connector parts 18 and then 17 onto the cable16 as shown in FIG. 2, has already been set forth. Now take the bodyassembly 19 set it to house the contact wedge assembly 17 whereupon thecontact pin 25 will slide fit in the central hole through the dielectricpartition 35 and extend into the socket 37. Then bring the lock and sealassembly 18 towards the lbody assembly 19 and turn the tubular screw4'!) to engage the threads 2% thereby drawing said lock and sealassembly 13 into said body assembly 19 which will cause the flared endof the tubular conductor 26 and its outer insulation covering 14 to besecurely clamped and will cause further compression of the ring gaskets43 and 46 to effect seals. It is important to note that during suchscrew-in of the tubular screw 4d, the side wall 41' of the groove 41will intercept the head 48 on the clamping ring 44, after which uponfurther movement of said tubular screw into the body assembly member 28,clamping action by the clamping ring 44 will increase, but there will beno further increase in the compression of the gasket rings 43 and 46.This provision is made particularly so that the gasket ring 43 shall notpress so hard against the cable 16 as would cause indentation of thedielectric 12 which is to be avoided in order not to impair theimpedance characteristic of the cable 16. Further note that said gasketring 43 is about the stem 23 which shields the dielectric 12 from beingdented and that the smallest diameter of the hole in said gasket ringpermitted is controlled because of the limited movement of the clampingring towards said gasket ring as is atforded by the stop bead 48. Alsoto be noted is that the compressed gaskets 43, 45 also act to eliminateall play in the thread joint at 23", thereby creating good frictionalhold against the loosening of the tubular screw 40 from the assembledconnector 15.

To position the contact wedge assembly 17 into the body assembly 19, theend boss 22" of the piece 22 which holds the terminal pin 25therethrough, fits in the inner socket in the sleeve 35. To limit themovement of the contact wedge assembly 17 into said body assembly 19, ametal ring 50 fits tightly on and about the sleeve 36,

d contacts the tubular member 35 and said ring serves as the stopagainst the rim of the part 2i. A flange 25" on the pin 25, located saidpin in the contact wedge assembly 17, by serving as a stop against thedielectric piece 22.

The continuity of contact from the tubular conductor 26 to thefrusto-conical member 20, to either or both the tubular member 28 andsaid ring 50 and then to the end member 35, makes the latter theterminal of the connector 15 which is for the tubular conductor 26 ofthe coaxial cable 16. The size of the connector 15 is primarilydetermined by the diameter of the cable 116 and of course, the insidediameter of the stem 23 shall allow a slide fit thereinto for thedielectric 51 of the cable.

This invention is capable of numerous forms and various applicationswithout departing from the essential features herein disclosed. It istherefore intended and desired that the embodiment herein shall bedeemed merely illustrative and not restrictive and that the patent shallcover allpatentable novelty herein set forth; reference being had to thefollowing claims rather than to the specific description herein toindicate the scope of this invention.

I claim:

1. In an electrical connector for a coaxial cable of the type includinga solid tubular dielectric having an inner conductor fittingtherethrough and at least an outer tubular conductor covering along saiddielectric, an electrically conductive tapered funnel element forslidably receiving therein the end portion of the tubular dielectric ofthe cable whereby said element shall lie between said dielectric and theouter tubular conductor of the cable and shall contact said outerconductor, the extending bare end of the inner conductor extending outof said element, a conductive tubular assembly including a tubularmember positioned about and electrically connected to said element meanswithin said tubular member acting as a stop to limit the movement ofsaid element into said tubular member and a clamp and seal assemblycomprising a sleeve to receive the cable, having a counterbore thereinin the end thereof facing the end of the cable, a clamping ringextending part way into said counterbore, said ring having an outwardflange around the end thereof which is outside of said counterbore, saidsleeve and ring being in slidable relation, said ring serving whenshifted towards the end of the cable when the cable is associated withsaid tapered element, to cooperate with said tapered element to clampthe outer tubular conductor of the cable between them, a sealing gasketring within said counterbore between said ring and the seat of saidcounterbore, adapted when compressed to contact the outside of thecable, another sealing gasket ring about said clamping ring between thesleeve and the flange on the clamping ring, adapted when compressed, toseal the space between said sleeve and said conductive tubular member,said tubular member having part of the sleeve therein and in telescopicrelation therewith, cooperative means on said sleeve and said tubularmember to hold them together to maintain said grip effectively andcooperative means on said sleeve and clamping ring to limit the extentof their relative sliding movement thereby limiting the compression ofsaid sealing gaskets.

2. An electrical connector as defined in claim 1, wherein saidcooperative means on the sleeve and tubular member to hold them togetheris aiforded by having said sleeve and associated tubular member inthreaded engagement.

3. An electrical connector as defined in claim 1, wherein thecooperative means on said sleeve and clamping ring to limit theirrelative sliding movement is aiforded by providing one of them with anannular groove of predetermined width and the other with'a protuberanceextending into said groove.

4. An electrical connector as defined in claim 3, wherein saidprotuberance is an annular bead.

5. In an electrical connector for a coaxial cable of the type includinga solid tubular dielectric having an inner conductor fittingtherethrough and at least an outer tubular conductor covering along saiddielectric, a contact Wedge assembly comprising an electricallyconductive tapered funnel element having a hollow stem for slidablyreceiving therein the end portion of the tubular dielectric of the cablewhen said stem is slid onto an end of the cable to lie between saiddielectric and the outer tubular conductor of the cable to an extentthat the tapered funnel part of said element is within and in contactwith the outer conductor of the cable, a dielectric element mounted insaid funnel part and carrying a conductive pin therethrough coaxiallywith said funnel element andextending away from out of the mouth of saidfunnel element; said pin being hollow and open at its end which istowards the stem of the funnel element wherein it is adapted to receiveinto such hollow, the extending bare end of the inner conductor of thecable when said dielectric of the cable is entered into said stem, atubular assembly including a conductive tubular member positioned aboutsaid contact wedge assembly, said tubular member being electricallyconnected to said funnel element, means within said tubular memberacting as a stop to limit the movement of said contact wedge assemblyinto said tubular member and a clamp and seal assembly comprising asleeve on the cable having a counterbore therein in the end thereoffacing the end of the cable, a clamping ring extending part Way intosaid counterbore, said ring having an outward flange around the endthereof which is outside of said counterbore, said sleeve and ring beingin slidable relation, said ring serving when shifted towards the end ofthe cable to cooperate with said tapered element to clamp the outertubular conductor of the cable between them when the cable is associatedwith said tapered element, a sealing gasket ring within said counterborebetween said ring and seat of said counterbore, adapted when compressedto contact the outside of the cable, said gasket sealing ring encirclingthe stem of the funnel element, another sealing gasket ring about saidclamping ring between the sleeve and the flange on the clamping ring,adapted when compressed, to seal the space between said sleeve and saidconductive tubular member, said tubular member having part of the sleevetherein and in telescopic relation therewith, cooperative means on saidsleeve and said tubular member to hold them together to maintain saidgrip effectively and cooperative means on said sleeve and clamping ringto limit the extent of their relative sliding movement thereby limitingthe compression of said sealing gaskets.

6. An electrical connector as defined in claim 5, wherein saidcooperative means on the sleeve and tubular member to hold them togetheris afforded by having said sleeve and associated tubular member inthreaded engagement.

7. An electrical connector as defined in claim 5, wherein thecooperative means on said sleeve and clamping ring to limit theirrelative sliding movement is afforded by providing one of them with anannular groove of predetermined width and the other with a protuberanceextending into said groove.

8. An electrical connector as defined in claim 7, wherein theprotuberance is an annular bead.

9. An electrical connector as defined in claim 5, wherein the surface ofsaid tapered funnel part is serrated.

10. An electrical connector as defined in claim 5, including adielectric liner in said tubular member; said liner having a partitiontherein intermediate its ends, said partition having a central holethrough which said pin is positioned and extends therefrom, thedielectric element carried Within said funnel part extending into saidliner and substantially fitted therein and a metal ring tightly on andabout said liner, contacting said tubular member and serving as a stopfor the rim of said funnel part.

References Cited in the file of this patent UNITED STATES PATENTS2,443,635 Norris et a1 June 22, 1948 2,615,953 Waite Oct. 28, 19522,761,110 Edlen et al. Aug. 28, 1956 2,870,420 Malek Ian. 20, 19592,986,720 Chess May 30, 1961 3,054,981 Malek et a1 Sept. 18, 1962

1. IN AN ELECTRICAL CONNECTOR FOR A COAXIAL CABLE OF THE TYPE INCLUDINGA SOLID TUBULAR DIELECTRIC HAVING AN INNER CONDUCTOR FITTINGTHERETHROUGH AND AT LEAST AN OUTER TUBULAR CONDUCTOR COVERING ALONG SAIDDIELECTRIC, AN ELECTRICALLY CONDUCTIVE TAPERED FUNNEL ELEMENT FORSLIDABLY RECEIVING THEREIN THE END PORTION OF THE TUBULAR DIELECTRIC OFTHE CABLE WHEREBY SAID ELEMENT SHALL LIE BETWEEN SAID DIELECTRIC AND THEOUTER TUBULAR CONDUCTOR OF THE CABLE AND SHALL CONTACT SAID OUTERCONDUCTOR, THE EXTENDING BARE END OF THE INNER CONDUCTOR EXTENDING OUTOF SAID ELEMENT, A CONDUCTIVE TUBULAR ASSEMBLY INCLUDING A TUBULARMEMBER POSITIONED ABOUT AND ELECTRICALLY CONNECTED TO SAID ELEMENT MEANSWITHIN SAID TUBULAR MEMBER ACTING AS A STOP TO LIMIT THE MOVEMENT OFSAID ELEMENT INTO SAID TUBULAR MEMBER AND A CLAMP AND SEAL ASSEMBLYCOMPRISING A SLEEVE TO RECEIVE THE CABLE, HAVING A COUNTERBORE THEREININ THE END THEREOF FACING THE END OF THE CABLE, A CLAMPING RINGEXTENDING PART WAY INTO SAID COUNTERBORE, SAID RING HAVING AN OUTWARDFLANGE AROUND THE END THEREOF WHICH IS OUTSIDE OF SAID COUNTERBORE, SAIDSLEEVE AND RING BEING IN SLIDABLE RELATION, SAID RING SERVING WHENSHIFTED TOWARDS THE END OF THE CABLE WHEN THE CABLE IS ASSOCIATED WITHSAID TAPERED ELEMENT, TO COOPERATE WITH SAID TAPERED ELEMENT TO CLAMPTHE OUTER TUBULAR CONDUCTOR OF THE CABLE BETWEEN THEM, A SEALING GASKETRING WITHIN SAID COUNTERBORE BETWEEN SAID RING AND THE SEAT OF SAIDCOUNTERBORE, ADAPTED WHEN COMPRESSED TO CONTACT THE OUTSIDE OF THECABLE, ANOTHER SEALING GASKET RING ABOUT SAID CLAMPING RING BETWEEN THESLEEVE AND THE FLANGE ON THE CLAMPING RING, ADAPTED WHEN COMPRESSED, TOSEAL THE SPACE BETWEEN SAID SLEEVE AND SAID CONDUCTIVE TUBULAR MEMBER,SAID TUBULAR MEMBER HAVING PART OF THE SLEEVE THEREIN AND IN TELESCOPICRELATION THEREWITH, COOPERATIVE MEANS ON SAID SLEEVE AND SAID TUBULARMEMBER TO HOLD THEM TOGETHR TO MAINTAIN SAID GRIP EFFECTIVELY ANDCOOPERATIVE MEANS ON SAID SLEEVE AND CLAMPING RING TO LIMIT THE EXTENTOF THEIR RELATIVE SLIDING MOVEMENT THEREBY LIMITING THE COMPRESSION OFSAID SEALING GASKETS.